1. Field of the Invention
The present invention relates generally to a display device. More particularly, the invention relates to a pixel circuit, a method of driving the pixel circuit, and an organic light emitting display device having the pixel circuit.
2. Description of the Related Art
An organic light emitting display (OLED) device includes a plurality of scan-lines, a plurality of data-lines, and a plurality of pixel circuits that are arranged in a matrix form at crossing points of the scan-lines and the data-lines. Each pixel circuit includes a driving transistor that controls a current flowing through an organic light emitting diode.
However, due to hysteresis characteristics of the driving transistor, a current flowing through the organic light emitting diode (i.e., a current controlled by the driving transistor) may be influenced by a data voltage of a previous frame. As a result, a non-uniform luminance may be caused among the pixel circuits, even when the same data voltage is applied to the pixel circuits.
Generally, each threshold voltage of driving transistors in the OLED device may be compensated in order to improve luminance uniformity. However, threshold voltage compensation may be insufficiently achieved within a short data programming time period if a data programming operation and a threshold voltage compensating operation for the driving transistors are performed at the same time.